1. Technical Field
The present invention relates to a printing method and a printing apparatus.
2. Related Art
Among ink jet printers, there is a type that uses large-sized paper sheets having a size that is equal to or larger than A2. In such ink jet printers used for large-sized paper sheets, a roll paper is frequently used in addition to single printing sheets. Hereinafter, it is assumed that a roll paper is acquired by winding paper into a roll body, and pulling out a part from the roll body, which is referred to as a paper sheet. The pulling of the paper sheet from the roll body is performed by driving a transport roller to rotate using a paper transporting motor (PF motor). The PF motor is controlled using PID control. An example of a printer that uses the above-described roll body is disclosed in JP-A-2007-290866. In addition, as an example of printers that perform the PID control, there are the printers that have been disclosed in JP-A-2006-240212, JP-A-2003-79177, and JP-A-2003-48351.
Commonly, the transport roller is set to be separated from the roll body, that is installed to a printer main body, by a predetermined distance in a direction in which a paper sheet is supplied. Accordingly, there are cases where a paper sheet that is pulled out from the roll body is loosened between the roll body and the transport roller. For example, when printing has started, a user performs an operation for pulling out a paper sheet from the roll body, that is installed in the printer main body, and setting the paper sheet to a paper transporting mechanism that is configured by a PF motor, a transport roller, and the like. However, at that moment, there are cases where the paper sheet is loosened between the roll body and the paper transporting mechanism. In addition, there are cases where a paper sheet is fed back (that is, rewound to return) in order to adjust the lead of the paper sheet after the paper sheet is set in a paper transporting mechanism, and also at that moment, there are cases where the paper sheet is loosened. When a printing process is performed using the loosened paper sheet, a printed image is disturbed so that the image quality deteriorates. Thus, commonly, the user checks for such looseness. When the paper sheet is determined to be loose, for example, the user rotates the roll body so as to wind the loosened portion of the paper sheet. As described above, in a printer that uses the roll body, a user needs to eliminate the looseness of the paper sheet manually, and there is a problem that time is needed to eliminate the looseness of the paper sheet. In addition, when the looseness is missed or the looseness cannot be eliminated sufficiently, the printed image may be disturbed.